In 2021, the retail price of a 1-carat lab-grown diamond can reach up to more than 30,000 yuan. Natural diamonds of the same color and quality are several times more expensive. At that time, there was an endless stream of customers lining up in front of the jewelry counter to try on lab-grown diamond rings. This year, the retail price of the same 1-carat high-quality cultivated diamond has dropped to about 3,500 yuan, a price reduction of nearly 90%.
Recently, there have been many heartbreaking buyer stories circulating on the Internet. Some people bought cultured diamond jewelry for 14,000 yuan, but now the recycling price is only 200 yuan, with a depreciation rate of up to 99%. Netizens laughed at themselves: "If I had known about it, I would have bought gold."
Just when brides regard lab-grown diamonds as a consumption trap and avoid it, the opposite scene is happening in Silicon Valley on the other side of the ocean.
Jensen Huang, CEO of NVIDIA, the global leader in AI computing power, is sending a team around the world to search for this kind of cultivated diamonds that are disliked by the wedding market and are even called "industrial scraps."
How did Stone, abandoned by the myth of love, transform into the new darling of Silicon Valley?
01AIsave diamonds
As of June, Huang Renxun has visited China twice in 2026. This technology giant, who is nicknamed "the shovel seller in the AI era", attracts much attention every time he travels to China. His consistent "shopping and eating" style always arouses heated discussions. But unlike the image of a "food blogger" in the public's mind, he actually carries an extremely important mission every time he comes to China.
Most of the people who met him were practitioners in the technology industry, but in a mysterious meeting at the beginning of this year, Huang Renxun met someone who surprised the outside world.
On January 25, he came to Beijing in a low-key manner and arranged a secret meeting on an undisclosed schedule. The person who met him was Zhu Yanhui, the founder of Chaoying Diamond Technology. Chaoying Diamond is a joint-stock company of Huanghe Tornado, an established diamond giant in Henan.
After the meeting, Zhu Yanhui posted a photo with Huang Renxun on Moments, instantly causing an earthquake in the semiconductor and capital circles.
As we all know, NVIDIA occupies an absolute dominance in the AI chip market. In 2025, its GPU (graphics processing unit) will account for 75.9% of AI servers. China’s advantages in the field of cultivated diamonds are also significant. The global rough production capacity of cultivated diamonds is about 40 million carats, and China contributes 25.2 million carats, accounting for about 63%. 95% of the world's artificial diamonds are produced in China, and 95% of China's artificial diamonds are produced in Henan.
When the two "world's number one" come together, the story of artificial diamonds takes a twist and turns into a new plot. The diamonds that were originally piled in a warehouse in Henan, waiting to be made into rings, suddenly became a strategic material urgently needed in Silicon Valley.
In fact, before Huang Renxun took action, lab-grown diamonds also experienced a roller coaster-like price fluctuation.
Lab-grown diamonds were once the top celebrity in the jewelry circle.
Around 2018, this kind of "replacement light", which has the same chemical composition and physical properties as natural diamonds but is half the price, entered the country, allowing the working class to grit their teeth and easily achieve "carat freedom." On social media, the topic "Can you buy lab-grown diamonds?" has attracted hundreds of millions of views. Countless girls preparing to get married have posted their first "diamond ring grown in a laboratory" on Xiaohongshu. The most common word in the text is "really fragrant."
This trend will completely explode in 2021. In the capital market, Henan diamond giants Huanghe Tornado and Zhongbing Hongjian soared by 209% and 166% respectively within a year; Power Diamond, which had just landed on the GEM, saw its stock price soar from 20.62 yuan to 250 yuan on the first day, becoming a super dark horse. At that time, the gross profit margin of Power Diamond was as high as 81.38%, which was almost equivalent to earning 8 from selling 1 diamond.
A factory owner in Henan recalled: "At that time, there was no need to visit customers at all. Customers came to the factory with cash and queued up to wait for the goods. A one-carat polished diamond was ordered before it was cut out."
Established jewelers such as Chow Tai Fook could no longer sit still and launched CAMA, a sub-brand of cultivated diamonds focusing on young people and digitalization, with high profile.
However, the golden period belonging to this wealth-making myth was shorter than anyone expected.
Huge profits attracted countless capital, and production capacity quickly got out of control. In Zhecheng, Henan, a small county known as the "Diamond Capital of China", dozens of large and small lab-grown diamond factories popped up overnight. From 2020 to 2023, China's lab-grown diamond output will grow at an average annual rate of 94.3%. Production is like a rocket, but consumer demand cannot keep up.
The ending was tragic.
The backlog of inventory has triggered a price stampede, and oversupply has caused the wholesale price of cultured diamonds to drop to a few hundred yuan per carat, which is not as expensive as a hot pot meal. Chow Tai Fook quietly shut down the CAMA brand and responded that "the group has no plans to develop cultivated diamonds." Huanghe Tornado has lost more than 2.6 billion yuan in three years, and Power Diamond’s gross profit margin has also been cut in half. A dealer said: "In the past, we sold based on carats, then we sold based on grams, and then we sold based on piles." Is the price plummeting mainly because supply exceeds demand?
The lovers in front of the jewelry counter turned and left. On social platforms, the topic of "regret for cultivated diamonds" quietly replaced "really fragrant". Lab-grown diamonds seem to have completely become a “bubble that no one wants.”
Until the heat dissipation crisis of AI chips brought an unexpected turn to the industry.
02Put a "fever-reducing patch" on the AI chip
Just as the factory owners in Henan were unable to sleep because of the backlog of diamond inventory, Huang Renxun in Silicon Valley was also worried about one thing and could not sleep all night.
What makes him sleepless is not the order of GPU (graphics processing unit), but the limit of physics, temperature.
The power consumption of a single chip of NVIDIA's latest generation Vera Rubin architecture AI chip has soared to an astonishing 2300W. What is this concept? In our daily life, when a household induction cooker is turned on to maximum heat, the power consumption is only a little over 2000W.
This means that on a silicon-based chip the size of a fingernail, its instantaneous heat output is equivalent to that of a fully powered induction cooker.
Traditional heat dissipation materials, copper and aluminum, are unable to cope with this kind of heat. The thermal conductivity of copper is about 400W/(m·K), while that of aluminum is only over 200. When the AI cluster is running at full speed, heat cannot be exported instantly, and the core temperature of the chip will hit a temperature wall of 110°C within a few minutes, forcing it to automatically reduce the frequency. The computing power is greatly reduced, and the training efficiency of large models with trillions of parameters is extremely low.
The industry has gradually reached a consensus that when the power consumption of a single chip exceeds 1000W or even approaches the limit of 2000W, traditional liquid cooling is no longer enough, and diamond (the finished product of gem-grade diamond after cutting, grinding and polishing is diamond) becomes the best heat dissipation material.
In terms of physical properties, diamond has a thermal conductivity as high as 2200W/(m·K) at room temperature due to its extremely tight and lightweight covalent bond network of carbon atoms, which is 5.5 times that of copper and 11 times that of aluminum. Its lattice vibration efficiency is extremely high. It can not only absorb and diffuse heat instantly, but also has excellent electrical insulation. Its thermal expansion coefficient is highly matched with the silicon chip, and the chip will not be broken due to the alternation of hot and cold.
In the eyes of semiconductor physicists, diamond is not a luxury product, but a perfect "fever-reducing patch" for AI chips.
In January this year, Nvidia clearly announced at CES that the next generation Vera Rubin architecture GPU will fully adopt the "diamond copper composite material + liquid cooling" solution. Then in February, the world's first NVIDIA H200 server equipped with Diamond Cooling diamond cooling technology was delivered to an Indian sovereign cloud service provider and put into operation. Diamond cooling entered commercial AI data centers from laboratories. In March, Akash Systems announced the launch of a diamond-cooled server equipped with AMD MI350X GPU, commercializing this technology on NVIDIA and AMD dual platforms.
Almost at the same time, Huang Renxun started a trip to China and communicated with Chaoying Diamond Technology.
03Henan factoryCatch the wealth and wealth from the sky
The wealth and wealth are thrown down from the sky, let's see who can catch it next.
The news spread back to China, and the capital market was the first to boil. As of the end of May this year, the Wind cultivated diamond concept index has increased by more than 90% year-to-date, and many stocks such as Power Diamond, Sifangda, Huanghe Tornado, and Huifeng Diamond have increased by more than 100% during the year. The total market value of the eight constituent stocks reached 141.7 billion yuan, a surge of 49 billion yuan from the beginning of the year.
In the past, most of the diamonds produced in Henan were jewelry-grade diamonds made using the HPHT method. To transform into AI heat sinks, you need to switch to the CVD method, which requires extremely high material purity (impurities less than 1 ppb), and the certification cycle is often as long as two or three years.
However, there are already Chinese companies leading the way.
The Yellow River Cyclone has undergone a stunning technological U-turn. In the past, it relied heavily on marriage and love consumption, not only supplying big brands such as Chow Tai Fook and Tiffany, but also signing five-year strategic long-term orders.
When the romantic bubble burst, it decisively transformed its high-luxury jewelry production line into a battlefield for hard-core technology. Now its contact window has been changed from jewelry buyers to technical experts from Huawei, SMIC, and NVIDIA. In February this year, Huanghe Tornado put into operation China’s first 8-inch diamond heat sink production line. Although the initial investment was huge and the financial statements still showed losses, the stock price has nearly doubled during the year.
Another Henan leading company, Power Diamond, relies on its deep financial strength. Its semiconductor heat sink successfully passed the official test of NVIDIA laboratory, becoming the only local listed company in China certified by NVIDIA. When the price of jewelry-grade diamonds plummeted, Power Diamond relied on its stable industrial diamond base and announced a high-profile announcement of the addition of 400 MPCVD equipment and plans to double its semiconductor heat sink production capacity to 1 million pieces per year, vowing to seize the technological high ground on the eve of the explosion of the semiconductor Red Sea.
Factory owners in Henan are working at an unprecedented speed to carve this small stone, originally used to be embedded in rings, into the cornerstone of Silicon Valley that supports the fourth industrial revolution.
Regarding lab-grown diamonds, the love story can no longer be told, but the technological story has just begun. The stone that was once abandoned by the myth of love finally found its real stage.